# US 4,396,083 A · Disconnectable hydraulic steering assistor > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 4,396,083 A - Document ID: US4396083A - Status: Granted - Kind: A - Application number: 06/173,260 - Filed: 1980-07-29 - Granted: 1983-08-02 - Earliest claimed: 1979-08-03 - Assignees: O&K Orenstein & Koppel Aktiengesellschaft - Inventors: Manfred Wehberg - Web page: https://patentgrep.com/patent/US4396083A ## CPC - B62D 5/065: characterised by specially adapted means for varying pressurised fluid supply based on need, e.g. on-demand, variable assist - B62D: MOTOR VEHICLES; TRAILERS (steering, or guiding on a desired track, of agricultural machines or implements A01B69/00; wheels, castors, axles, increasing wheel adhesion B60B; vehicle tyres, tyre inflation or tyre changing B60C; connections between vehicles of a train or the like B60D; vehicles for use on rail and road, amphibious or convertible vehicles B60F; suspension arrangements B60G; heating, cooling, ventilating or other air treating devices B60H; windows, windscreens, non-fixed roofs, doors or similar devices, protective coverings for vehicles not in use B60J; propulsion plant arrangements, auxiliary drives, transmissions, controls, instrumentation or dashboards B60K; electric equipment or propulsion of electrically-propelled vehicles B60L; power supply for electrically-propelled vehicles B60M; passenger accommodation not otherwise provided for B60N; adaptations for load transportation or to carry special loads or objects B60P; arrangement of signalling or lighting devices, the mounting or supporting thereof or circuits therefor, for vehicles in general B60Q; vehicles, vehicle fittings or vehicle parts not otherwise provided for B60R; servicing, cleaning, repairing, supporting, lifting, or manoeuvring, not otherwise provided for, B60S; brake arrangements, brake control systems or parts thereof B60T; air-cushion vehicles B60V; motor-cycles, accessories therefor B62J, B62K; testing of vehicles G01M) ## Abstract A hydraulic steering assistor, which can be switched off, for a vehicle with a hydraulic pump, an electric motor and a relay, which vehicle is driven by an electromotor, runs on wheels and is actuated by means of a drive control. By means of a switch disposed in the drive control, the motor of the hydraulic pump for the steering assistor is turned on through a time relay (having an activatable delay time) and another relay, and during the rotation of the armature shaft of the electromotor of the vehicle the time relay receives pulses from a pulse generator in the electromotor preventing the activation (initiation) and thus expiration of the delay time, and the pump driving motor for the steering assistor is stopped only after the absence of the pulses while in the neutral position, causing activation of the time relay and then after expiration of the delay time, by means of the drive control and opened switch. ## Claims ### Claim 1 In a disconnectable hydraulic steering assistor for a vehicle with a hydraulic pump, an electric motor therefor and a relay operatively connected together, the vehicle being driven by an electromotor, running on wheels and being actuated by means of a drive control means, the improvement comprising a time relay means, operatively connected to said hydraulic pump in turn via the first-mentioned relay and the electric motor, switch means disposed in the drive control means and when closed for turning on the electric motor of the hydraulic pump for the steering assistor via said time relay means and said first-mentioned relay, said time relay means for turning off the electric motor of the hydraulic pump for the steering assistor via the first-mentioned relay when said time relay means is activated after expiration of a time delay thereof, said electromotor has an operative armature shaft, said armature shaft being operatively connected to said electromotor so as to rotate when said vehicle is moving, pulse generator means operatively disposed in said electromotor for transmitting pulses to said time relay means when said armature shaft rotates, said time relay means for being unactivated when said pulses are received by said time relay means for preventing the expiration of the time delay and for keeping the electric motor of the hydraulic pump turned on via said first-mentioned relay, said pulse generator means for stopping said pulses when said armature shaft is stationary, said drive control means in a zero inoperative position thereof for opening said switch means, said time relay means, in said zero inoperative position with said switch open and when said pulses are stopped, for being activated, whereby the electric motor of the hydraulic pump for the steering assistor after the expiration of said delay time is turned off. ### Claim 2 (depends on 1) The steering assistor as set forth in claim 1, wherein said time relay means includes a capacitor. ### Claim 3 (depends on 2) The steering assistor as set forth in claim 2, wherein said switch and said pulse generator are connected in parallel to each other and in series between a voltage source and said time relay means. ### Claim 4 (depends on 1) The steering assistor as set forth in claim 1, wherein said drive control means is operatively connected to said electromotor for rotating said armature shaft when said drive control means is in a driving position. ### Claim 5 A method for turning on and off a disconnectable hydraulic steering assistor for a vehicle with a hydraulic pump, an electric motor therefor and a relay operatively connected together, the vehicle being driven by an electromotor, running on wheels and being actuated by means of a drive control, comprising the steps of in an operative driving condition of the vehicle automatically turning on the electric motor of the hydraulic pump for the steering assistor via a time relay and in turn the first-mentioned relay, by energizing the time relay and thereby the first-mentioned relay, in an inoperative driving condition of the vehicle automatically sending pulses to the time relay upon rotation of the electromotor of the vehicle by movement of the vehicle, by means of a pulse generator such that the electric motor of the hydraulic pump is turned on, and preventing activation of the time relay and turning off of the electric motor of the hydraulic pump by the pulses sent to the time relay, in another inoperative driving condition of the vehicle with the vehicle stationary, stopping the electric motor of the hydraulic pump for the steering assistor by activating the time relay and after expiration of a delay time thereof, by first stopping the pulses by non-rotation of the electromotor, at neutral position of the drive control. ### Claim 6 (depends on 5) The method as set forth in claim 5, wherein in the operative driving condition performing the energizing of the time relay by closing a switch connecting direct voltage to the time relay, and in the inoperative driving condition opening the switch.